The number of women on corporate boards in Maryland increased last year, and for the first time, all businesses that joined the state's publicly traded companies had at least one woman board member, Network 2000 said in a report released Wednesday.

The number of women on boards rose to 86 from 73 at the state's 76 publicly traded firms, the group said in its annual Census of Women Board Directors in Maryland. The number of women of color rose as well to 15 from 11.

The increase is encouraging, "especially when one considers that for several years there has been little progress," said Katherine Bays Armstrong, president of Network 2000, a local group that works to increase the number of women in boardrooms and executive suites, in the report's introduction. "I'd like to think that this improvement is due to the growing awareness among corporate leaders that gender diversity is good for business — aside from being the right thing to do."

The share of women on boards also increased, to 13.3 percent last year from 10.7 percent in 2012, though the number of total board seats declined to 646 last year from 683 in 2012.

The number of companies in which women represented 20 percent or more of the board was up to 18, from 15, and included firms such as Ciena Corp., Lockheed Martin Corp., Sandy Spring Bancorp and W.R. Grace & Co., while the number of firms without women directors fell to 22 from 31. Companies without women on the board or in executive roles declined significantly for the third year in a row.